High-power gas heating apparatus



June 12, 1934. wU 1,963,009

' HI :H POWER GAS HEATING APPARATUS/ Filed Dec. 8, 19:0 ZSheets-Sheet 1lnvenfor'a' I I l men-rowan GAS HEATING APPARATUS Guido Wiinsch, erna-sima, Germany Application llecember 8; 1930. Serial In Germany December 9,192

10 Claims. (Cl. 158-109) 'I'hisinvention relates to high-power gasheating apparatus and more particularly to highpower gas burners for thewell-known Cowper apparatus of blast furnaces, for example. Cowperapparatus in use today for blast furnaces are very high-powered andrequire as much as 2000 or even more cubic meters of gas per hour. Suchlarge quantities of gas can be fed or supplied only where the' gas isblown into the combustion shaft of the Cowper under much higher pressurethan heretofore. however, ,presents the serious diflieulty that the gasand air mixture, by reason of the high pressure used,

acquires much too great a velocity relative to the igniting speed of thegas mixture. Asa result the flame cannot ignite quietly adhering to theopening of the gas and air mixture supply conduit in the combustionshaft, but continuously breaks or is torn away from said opening, thusgiving rise to the popping orsputtering of the flame so injurious to theoperation of the apparatus.

The invention has for its object, among other things, to overcome thisdifliculty by providing for a much more intimate admixture of the gaseswith ,the air, whereby the igniting speed of the gases is materiallyincreased, and also preferably by providing a suitable impediment orimpediments infront of the opening of the supply or feed conduit of thegas-air mixture into the combustion shaft. The gas-air mixture -breaksagainst said impediments, in the lee of which there is thus formedazone, or zones, of lower velocity, lower than the speed of ignition.Furthermore, behind the impediments the flow or stream of the gas-airmixture rapidly spreads over a materially greater crosssectional area.-The mean speed of flow thus drops below the igniting speed. allowing theflame to ignite quietly in the lee of the impediments. A'quiet flamefilling the combustion shaft is thus secured without the impedimentsdiminishing in any degree the amount 01 the air and gas mixturesupplied.

The invention and its aims and objects will be best understood from thefollowing description,

purposes, the true scope of the. invention being more particularlypointed out in the appended claims.

Iii the drawings:

Fig. 1 shows a Cowper'of conventional con-.

"inotor 9 (see Fig. 1).

taken in connection with the accompanying drawings of one embodiment ofthe invention herein described and shown for illustrative 'structionwith an illustrative embodiment of the invention, partly in section;

Fig. 2 is a longitudinal sectional elevation of the air conduit, withthe inserted gas pipes;

Fig. 3 is an end view of the construction shown. 9 in Fig. 2, viewedfrom the right of the latter Fig. 4 is an'illustrative embodiment of animpedin'ient in accordance with the invention;

Fig. 5 is a further illustrative embodiment of an impediment inaccordance with .the inven: tion;

Fig. 6 shows a part of the. combustion shaft with the impedimentillustrated in Fig. 5.

The intimate mixture of the gas with the combustionair may be secured invarious ways and by various means, without departing from. the spirit ofthe invention. In the Cowpers commonly used today the combustion airconduit and the gas conduit .are surrounded one by the other at theiropening into the mixing chamber in such manner that .one conduit opensinto the other in form of a suction jet. In the case of Cowper burnersof this type the mixture of gas and combustion air can be secured in thesimplest way by providing openings in the inside conduit through whichthe medium flowing through the outer conduit is sucked by the. action ofthe medium flowing through the inner conduit. Parts of the gases flowingthrough the outer conduit thus penetrate into the innermost core, of theinner gas'conduit,

'thus producing a much more intimate mixture than it was possible toproduce heretofore.

Referring to the drawings, the gas mixture 0 supply conduit 2 opens intothe combustion shaft 1 of the Cowper. The combustion gas is suckedthrough the gas conduit 3. Tim air supply conduit 4 is inserted inthe/usual manner within the gas conduit 3. The combustion air issupplied under pressure by a fan '9a. driven by a To change over theCowper from the heating period' to' the draft period there are used, asusual, quickly operable slide dampers 5 and 6, the former of whichcloses oil! the Cowper from the gas and air mixture, whereas the slide 6serves to shut oi! the gas conduit itself.

For the operation of said slide dampers 5 and 6 there are provided acrank 7 and a hand 1 wheel 8. a p The parts described in the aboveparagraph are of conventional and well known construction and need notbe more fully described.

I will now describe means for securing the vided more intimate mixtureof the combustion gases. In the illustrative embodiment of the inventionsaid means comprises ports 11 provided in the wall of the inner conduit4, which in the illustrative embodiment of the invention supplies thecombustion air. In said ports 11 are proorwardly inclined pipes 12 whichare preferably welded in place. The current of combustion air driventhrough the air supply conduit 4 by operation of the fan 9a sucks thegas from the conduit 3 through said pipes 12 directly forwardly towardsthe centre of the combustion air stream, said gas thus penetrating tothe innermost core of said combustion air stream. An extremely intimatemixture of the gas with the combustion air is thus secured. For thebetter distribution of the stream of combustion air within its conduit aspreading cone 10, having guiding surfaces 10a, may be provided. Themixture of gas and air then flows through the gas mixture supply conduit2 into the combustion shaft of the Cowper.

- While the ports 11 of the air supply conduit, by effecting a much moreintimate mixture of the gas with the combustion air, materially increase or raise the igniting speed of the mixture, the velocity of theflow of the gas and air mixture still exceeds said igniting speed, sothat a quiet flame does not yet form adhering -to the opening of thesupply conduit 2 into the combustion shaft 1. Means are accordinglyprovided in accordance with the invention for this purpose,'said meansin the illustrative embodiment of the invention comprising impedimentsas already set forth. Said impediments :may conveniently take the formof a grid. In

the illustrative form of grid shown in Fig. 4 said grid comprises aplurality of vertical rods vd spaced apart preferably a distance greaterthan the width of the rods. Said rods may be of any suitable material,preferably of iron, and their spacing from each other may be equal to amultiple of their width. Under some conditions it is preferable toprovide a second grid situated centrally of the grid (1, said second-grid consisting of a plurality of rods d1, d2,

In the lee of the grid rods there are formedcombustion shaft andextending transversely of the inner opening of said conduit, said gridbeing of relatively large mesh so as not to impair materially the,volume of flow of the gas and air mixture to the combustion shaft.

. 2. In apparatusof the class described,- in combination, a combustionshaft; a gas and air mixture conduit opening at its inner-end into saidcombustion shaft; a. gas supply tube and an air supply tubeconcentrically positioned for injecting a mixture of gas and air intosaid conduit through its outer end; means to-force air from atmospherethrough said air tube; and a grid extending transversely of the openingbetween the. inner end of said conduit and'said combustion shaft, saidgrid being of relatively .large mesh so as not to impair materially .thevolume of flow of the gas and air mixture to the combustion" shaft.

3. In apparatus of the class described, in combination, a combustionshaft; a gas supply conduit therefor; an air supply conduit for saidcombustion shaft; means cooperating with said conduits intimately to mixthe gas and air sup-' bination, a combustion shaft; a gas supply conduittherefo an air supply conduit for said combustion shaft; meanscooperating with said regions of lower velocity of flow of the gas and'conduits intimately t i th gas and air ,125

air mixture, in which the flame can ignite. By means of the grid the airand gas mixture is relatively quickly distributed over a widercrosssectional area, so that withina short distance at the 'rear of thegrid the mean velocity of flow of the air and gas mixture will be belowthe igniting speed of said gas mixture, so that the flame thatignites-against the grid rods twill burn quietly without being torn awaytherefrom. Y a

In the illustrative embodiment of the grid shown in Figs. 5 and 6, thegrid rods d3 radiate from a common central point and are preferably heldtogether at their inner ends bya dispersion cone e having its apexdirected towards the centre of the flow in the gas mixture supplyconduit 2. Said dispersion cone effects a still better and widerdispersion of the mixture of gas and air over a greater cross-sectionalarea within the combustion shaft 1.

I am aware that my invention may be embodied in other specific formswithout departing from the spirit or essential attributes of saidinvention, and I therefore desire the present embodiment to beconsidered in all respec s plied thereby, in their passage to saidcombustion shaft; and a grid extending transversely of the fiow of thegas and air mixture at its entrance into. said combustion shaft, saidgrid being of relatively large mesh so as not to impair materially thevolume of flow of the gas and air mixture to said combustion shaft.

5. In apparatus of. the class described, in i,

combination, a combustion shaft; a gas supply conduit therefor; an airsupply conduit for said combustion shaft; means cooperating with saidbination, a combustion shaft; a conduit opening at its inner end intosaid combustion shaft; means comprising gas and air supply tubes at theouter end of said conduit to inject a mixture of gas and air throughsaid" conduit into said combustion shaft; and means adjacent the innerend of said conduit and presenting upon one side areas of impact to thegas and air mixture flowing to the combustion shaft and upon theopposite side areas of adhesion for' the flame when said mixture isignited, said areas being spaced apart sufliciently not to impairmaterially the volume of flow of said gas and air mixtureto saidcombustion shaft.

7. In apparatus of the class described, in combination, a combustionshaft; gas and air supply tubes for injecting a mixture of gas and airinto said, combustion shaft; and means spaced from the dischargeopenings of said tubes in the direction of said combustion shaft andpresenting areas of impact to the gas and air mixture flowing with highvelocity to said combustion shaft to form in the lee of said areas,zones ofreduced velocity in which the mixture can ignite without theflame being torn awayby the high velocity flow of said mixture, saidareas being spaced apart sufliciently not to impair materially thevolume of flow ofv said gas and air mixture to said combustion shaft.

8. In apparatus of the class described, in combination, a combustionshaft; gas and air supply tubes for injecting a mixture of gas and airinto said combustion shaft; and a grid spaced from the dischargeopenings of said tubes in the direction of said combustion shaft, thegrid members being spaced apart sufficiently not to impair materiallythe volume of flow of the gas and air mixture to said combustion shaftand being of a cross section to form in the lee of said members zones ofreduced velocity in which the gas and air mixture can ignite without theflame being torn away by the high velocity of the flow of said mixture.

9. In apparatus of the class described, in combination, a combustionshaft; a conduit opening gas and air through said conduit into saidcombustion shaft; and a grid comprising a plurality of superposedintersecting bars, said bars being spaced apart sufiiciently not toimpair materially the volume of flow of said gas and air mixture to saidcombustion shaft, said grid being positioned across the opening of saidconduit into said shaft.

10. In apparatus of the class described, in combination, a combustionshaft; means to inject a mixture of gas and air into said combustionshaft; and means disposed in a plane transversely of the flow of saidgas and air mixture andpresenting areas of impact to said gas and airmixture as it flows with high velocity to said combustion shaft, to formin the lee of said areas zones of reduced velocity in which said gasandair mixture can ignite without the flame being torn away by the highvelocity of the flow of said mixture, said areas being spaced apartsufliciently not to impair materially the volume of flow of said gas andair mixture to said combustion shaft.

GUIDO wimscn.

